Flexible bearing for high-speed spindles.



G. A. OVEHSTHOM.

FLEXIBLE BEARING FOR HIGH SPED SPINDLES.

G. A. WERSTROM. nexnalz mams ron HIGH smo spmmes.

APPLICATION FILED MAY 9. 1916.

Patented July 23,1918.

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m 10. fam/17% /f/ WwW-fl GUSTAVE A. OVERSTROM, 0F PASADENA, CALIFOI LIIA.

FLEXIBLE BEARING F011 HIGH-SPEED SPINDLES.

Application tiled May 9, 1916.

To'all who/n` it ma concern Re it known t at I, (ies'ravn A. (lvnir srnou, a citizen of the llnited States, residing at Pasadena. in the county of Los Angeles` and State of (`alifornia, have invented a new and useful Flexible Bearing for High-Speed Spindles, of which the fol lowing is a specification.

This invention relates to hearings for high speed spindles` such as the spindles of centrifugal crushers. separators or other devices in which a shaft or spindle is driven at high speed and requires a hearing which is resiliently supported so as to enable it to whirl or spin with minimum strain or friction ou itsl bearings.

The main object of the present invention is to provide a flexible or resiliently supported hearing for the stated purpose, in which there will be a minimum of friction and wear. In this connection the invention provides for mounting the bearing without the use of relatively slippin or sliding parts so that the wear and friction due to movement of such parts is avoided.

Another object of the invention is to provide a resiliently supported bearing construction in which a plurality of springs are employed "and in which each spring is etective in sustaining lthe lateral stresses in any direction so that the full power of all the springs is utilized at all times.

The accompanying drawings illustrate embodiments of my invention, and referring thereto, Figure 1 is a vertical section of a portion of a centrifugal erusher embodying my invention.

Fig. 2 is a plan view of the Hexible bearing` therefor, with parts broken away.

ig. 3 is a vertical section of a modified form of the hearing.

yFig. 4 is a vertical section of another form of the invention, showing the motor mount-ed directly on the spindle.

Fig. 5 is a vertical section of another form of the invention.

Referring to Figs. 1 and 2, 1 designates a part of the frame of a centrifugal crusher rovided aty its lower portion with a lower caring support 2 supportinga lower bearing 3 and at its upper portion with a flexibly or resiliently supported bearing for the spindle 4 of the erusher, said spindle carrying at' its upper end any suitable form of inipeller, indicated at 5, adapted to receive the stones, etc., and to discharge them tan- Specitcation of Letters Patent.

Patented July 23, 1918.

Serial No. 96,275.

gentially at high velocity in the usual inanner. Lower hearings support 2 may be of any suitable construction, being herein shown as comprising a spherical bearing portion 2 and a lower end bearing portion 7 concentric with the center of said spherical bearing, the lower hearing 3 for spindle 4 being provided with bearing faces coperating respectively with said bearing por tions. Driring means, such as pulley 8, is mounted on spindle 4` and extends around the lower bearing portion Q so that tilting movement of the spindle on said hearing portion will not a fiect the driving operation.

The upper hearing for the spindle 4 is mounted within a tubular or cylindrical frame member l' carried by the frame portion 1. and comprises upper and lower supporting rings 5.) and 1U fitting within said frame member 1', springs 11 mounted be- `tween said upper and lower supporting members and upper and lower members 13 and llV carried by hearing means 15 and connected to said springs; Member 13 may, as shown. consist of a flange extending outwardly from said bearing means 15, which may consist, for example, of a` hub or sleeve provided with a lining in which the spindle 4 is adapted to rotate, and the lower member 14 may he fdlmed as a flange on a collar 16 keyed to said hearing means 15. Bolts 17 connect the upper and lower members 13 and 14` and extend through the springs 11, said springs being formed as spiral springs, the innermost turn of each spring closely fitting on the corresponding bolt` 17 and the outermost turn of each spring closely fitting within cylindrical recesses, seats or shoulders 19 formed on the respective members 9 and 10. Bolts 21 extend between the members 9 and 10 and clamp them rigidly on to the outermost portions of the respective springs 11. Said springs 11 are arranged around the spindle 4, there being as many of these springs as required to take up or sustain the pressures or stresses due to the revolution of the shaft at high speed when operating unler load. These springs are preferably spiral springs, each spring being formed of a strip of resilient sheet. metal coiled in the manner of a clock spring, and in the form of a true spiral. continually increasing its distance from the center from one end to the other, and with each turn surrounding the receding turn, as distinguished from a he ical spring. Earl: spring 1s, how- `ever, provided with innermost and outermost coils of substantially cylindrical shape adapted to tightly engage bolts 17 and shoulders 19 respectively. 'l`hc cylindrical shoulders 19 haye inturned portions 19 engaging the ends of said outermost coils to prevent longitudinal or axial displacement of said sprmgs relative to members 9 and 10. In order to provide the requisite radial resist- 10 ance without undue longitudinal stiffness of motion, that is to say, motion in a direction parallel to the axes of the springs, e plurality, for example two, springs may be provided around each bolt 17, an intern'xediate collar 18 extending between the springs and engaging the same in a similar manner to shoulders 19, said collar 18 being provided with an inward projection 18 engaging the ends ot' the outermost coils of the springs 20 similarly to portions 19. With the s rings arranged as shown in Fig. l any de ection of the shaft or spindle 4 from vertical p0- sition will result in vertical or endwise movement or displacement of the bolts 17 with relation to the supporting frame, and in this endwise movement the springs 11 must yield in such Vmanner that the inner portions of the springs move longitudinally or axially with reference" to their outer ortions. he resistance of such longtu inal ,for axial displacement increases with the 'height of the springs so that, by subdividing theils rings as shown, this resistance is diminls ed while at the same time the requisite radial stiffness is secured. p

ln order to prevent entrance of dust or dirt, etc., into the bearing, I refer to cover the same with an apron 24 o suitable liexible material, suchas leather, canvas, etc., fastened by means 25 on top of the cylindrical frame member l and secured at'its inner end hy snap rings 26 into an annular groove 27 on an upward extension 28 of the bearing means l5. A gasket or packing ring 29 on top of this bearing extension prevents entrance of dust, etc., at the top of the bearing. The apron 24 may bg, supported by a sheet metal disk or ring 31 secured on top of the frame member 1' and extending inwardly 5U beneath the said apron. The lower end of the cylindrical frame member 1 may be closedr hy an annular cup-shaped member 33 separated from the spindle 4 by a space indicated at 35 sullicient to allow the necessary play of the shaft, a collar 36 on said spindle extending over the inner wall` 33 of member 33 to shed any oil running down from the bearing into the annular cup-shaped member 33, whence it may be drainedl away by an outlet pipe 38 through suitable means for receiving the oil and pumping it back to the bearing. at 39 in the hase 40 of the frame 1 and an oil chamber 4l formed in said hase are connected by a pipe 42 to suitable oil pumping 'the springs equally operative at al Oil receiving means as indicated means and communicate through passages 43 with the lower hearing 2 and with a bore ing respectively at the top of the lower bearing 2 and at the upper portion of the upper bearing. -In the operation of the machine oil will pass from this upper aperture 46 to all parts of the upper bearing, and so much of the oil as passes t0 the top of the upper 75 bearin will escape through passages 47 in the bearing extension 28 and, runnmg down over the upper flange 13 and through the openings 4 therein, will lubricate all the parts of the spring 11 and the supporting s0 devices therefor.` Normally the spindle 4 is held in centralized positlon by the operation of all the springs 11 which connect the bolts 17 and the supporting members 9 and 10 in such 85 manner that said spindle is resiliently supported from the frame member 1 by each one of these springs. When the spindle 4 is rotated at high speed and the machine is in operation, material being received by and 9 thrown from the impeller 5 i'n the usual manner, there is a tendency fothe. spindle to press laterally on the upper caring, this lateral pressure varying in tension and in the direction .in which it is exerted but re- (piring at all times a resilient support to` t e bearngwhich will resist undue displacement of the spindle While 'permittipg sufficient' play or lateral movement thereof to prevent undue wear or friction on the bearing. The form ofspring shown, namely a spiral spring connected at its inner and outer portions to the supporting frame and to the shaft bearing,V is eminently adapted for this ur )ose as it enables each spring to exert its ull resilient restoring action on the spindlein whatever direction the latter yis laterally displaced, the construction being such that the action of the spring is the same in all directions. In devices of this character where coil sprin s have been used extending between the s aft bearing and lixed supporting means, lateral displacement of shaft results in effective action of the sprin or springs at only one side of the shaft, an the opposing springs counteract one anothen with the result that the springs have to be made unduly heavy and are not sutliciently responsive, or rapid in action to enable the bearing to accommodate itself to than motion of the shaft at all times. By making all 'of l" imes I am enabled to decrease the weightzpf the springs and to make them sullicien-t-ly sensiti ve and rapid in action tofollow a'll of the 125 movements of the spindle thereby reducing the strain and wear on the bearing to a minimum. This uniform action of each spring in all directions arises from the fact that the spring, being a spiral spring attached at its center to the bearing and at its periphery to the bearing support is subjected to similar defmmatiou whatever may be the directions of lateral displacement of the bearing relative to its support, and displace ment in any ('lircction will producen force tending to restore the parts to normal positlon.

As shown in Fig. 3 the spring members l1 may be so disposed that the axes converge to the center of gyratiou of the spindle 4, thereby obviating any endwise movement of the bearing and its support. The members 9', 10', 13 and 14', mounted respectively on the bearing and on the fixed support and engaging respectively with the center portions and with the peripheral portions of the respective springs, being in this case dished so as to extend at right angles to the axes of said Springs. The amical bushings 48 are provided at the lower ends of the center pins 17 to facilitate insertion of said pins, said taper bushing being seated in taper seats on a collar 16 mounted on the bearing member 15', in this case the center pins 17 extending through the respective coil springs and connecting them to the respective members 13' and 14 are held in position by collar 16.

In order to retain oil in contact with the springs, a packing ring 49 may be provided between the lower face of a Bange 50 on collar 16' and a flange 51 on the cup member 53 at the bottom of the frame member 1, so that oil passing from the bearing as above described, through the passage 47, will flood the spring parts and will overow through the passage 52 on the wall of bearing member 15.

Fig. 4 shows the application of the invention in connection with a centrifugal Crusher in which the motor, indicated at 55 is mounted on the spindle i so as to partake of the gyratory motion thereof, the lower hearing 56 of said motor being provided with means indicated at 57 for preventing rotation of the stator portion of the motor. A spindle 4 in this case constitutes the motor shaft' and is mounted to rotate relatively to the stator in any suitable manner. In this case springs indicated at 11 are arranged in pairs around the spindlefl, the springs of each pairbeing superimposed with a bolt 59 extending through the centers of each pair of springs and through upper and lower flanges on a bearing member 60 forming an u per bearing for spindle 4. The support or the springs in this case is shown as comprising upper and lower rings 61 and 62 provided with-seats 63for engaging and supporting the peripheral portions of the upper and lower springs, an intermediate ring 66 extending between the springs of cach pair and provided with seat portions 67 for engaging the peripheral portendency to relative.

bolts fitting and the springs l1 sfuirronnding` tionsthereo. The several rings 6l, 62, 66, fit within a cylindrical lining G9 mounted within the frame member l' and resting upon a shoulder 7, said lining having an inwardly extending flange 71 to receive the oil front-the bearing and direct it to an outlet 77.

In order to insure that the spring inem bers will he neutral or free from strain in the normal position of the spindle, I prcfer, in some cases, to mount the-n1 as shown in Fig. 5 in which the bolts 17 are mounted on collar members 13' and 14', similarly to the construction shown in Fig 3, with the exception that the said bolts are fitted in the upper collar 13 by taper beads on thc in taper sockets on the said collar, bushings 78 on said bolts are inclosed with-- in babbitt liningsl 79 which are cast between the springs and a cage member fitting. within the frame member l'. By pro i erly assembling the parts before the bai)- bitt is poured the springs will he supported in such relation that there is no 1ension in any direction on any of thc s wings in the normal position of the spindle, and uniA form action of ali the spring' in any displacement of the spindle is thereby insured.

In allof the above described embodiments of `my invention it is im 'iortant that the natural rate of vibration oi the spring or spring system should be in excess of the normal rate of revolution of the shaft. so that the spring will respond tto every lat eral movement of the shaft in time to pren veut excessive movement. By providing n plurality of springs arranged. around the shaft and all' operating simultancously in the same manner and normally neutral, that is to`say, Without strain when the shaft, is runnin in centralized position, the impor tant atif'antage is obtained that breakage or disabling of any spring docs not dcrcntrat 'ize the system or uubalance the action.

iVhat I claim is:

1. A flexible bearing for high speed spin dies comprising a supporting member, a bearing member for the spindle, and a series of spiral springs arranged in a circle about the center of the spindle, each of said springs consisting of a resilient metal strip coiled in a plurality of turns, each turn surrounding the preceding turn, and each spring engaging at its outcr cnd one of said members and engaging at its inner end the other of said members.

A flexible bearing for high Speed Spindles comprising a fixed member, a bearing' member for the s indle, supporting means on said fixed mem er, su porting means on said hearing member, and)a series of spiral springs arranged in different angular sitions around the center of the spindf; each of said springs consist'eg of a resilient metal strip coiled in the form of a lclock spring engaging at its outer portion one of said supporting means and engaging at its inner portion the other of said supporting means.

i A fiexible bearing for high speedspindles comprising fixed supporting means, bearing means for the spindle, supporting means mounted on said bearing means, and a series of spiral springs arranged in a circle around the center of said spindle, each `of said springs' consisting of a resilient metal strip coiled in the form of a clock spring, the outermost end portion of each of said sirings being eu a ed throurhout one comp ete turn thereo y one o said supporting means, and the innermost portion of each of said springs being engaged by the other of Said supporting means, so that radial motion of the spindle in any direction will be uniformly resiste-(1 by all the springs at all times.

4. A flexible bearing for hi h speed spin dles comprising a fixed'mem er, a fioating member, a series of cylindrical supporting devices symmetrically placed around the center of one of said. members and attached thereto, a series of bolts extending through said cylindrical supporting devices and attached to the other of said members, and a series of spring devices within said cylindrcal supporting devices and around said 5. A flexible bearing for high speed spindies comprising a sup orting memberz a hearing member for t e spindle, casing members on said supporting member disposed in different angular positions around the spindle, members extending `through said easing members and attached to said hearing member, and'spring devices within said casing members and around the members extendin therethrough.

(i. The com ination of a high speed spindle and a `flexible bearing therefor, said spindle being mounted to gyrate al'mut a center below said bearing, and said bearing comprising a fixed supporting member, a bearing member for the spindle, and a series of spiral springs disposed in different angular positions around' the spindle andengaging one of said members at their outer portions and engaging the other of said members at their inner portions, and Said springs having their axes extending radially with respect to said center about which the spindle gyrates.

In testimony whereof I have hereunto set my hand at Los` Angeles, California, this 2nd day of May, 1916.

GUSTAV A. ovERsTRoM. 

